O.S. Engine OSMG0845 FS-40S Four-Stroke Aeroplane Engine  [OSMG0845]

O.S. Engine OSMG0845 FS-40S - Reliable Four-Stroke for RC Aircraft

This four-stroke unit delivers dependable power for model aircraft pilots who prefer smoother throttle characteristics. As part of O.S. Engines Surpass Series, the FS-40S is tuned to handle heavier loads and larger-diameter props for varied flying styles.

Design Highlights from the Surpass Range

The Surpass range uses a helix gear-driven camshaft at the front with an updraft carburetor at the rear to maintain a consistent mixture and clean combustion. The FS-40S comes with a fitted glow plug and a standard silencer to simplify the first run and routine use.

Operational Performance Summary

Key dimensions include a displacement of 0.396 cu in, a bore of 0.835 in and a stroke of 0.724 in. The usable rpm band runs from 2,200 up to 12,000, producing 0.65 hp at the top end while keeping the overall weight near 12.5 ounces.

The FS-40S balances usable power with manageable weight, making it a strong pick for both scale model builds and sport aeroplanes. Regular basic service will keep it running smoothly season after season.